Zirconia-faced refractory



Patente Nov. 22, W21.

PAUL G. WILLETTS, O1? BERLIN, CONNECTICUT, ASSIGNOR TO HARTFORD- EMPIRE COMPANY, OF HARTFORD, CONNECTICUT, A CORPORATION OF DELAWARE.

z rnconra-raonn REFRACTORY.

No llrawing.

My invention relates torefractories and it has special reference to refractory blocks and other refractory bodies provided with facings of zirconium oxid.

The object of my invention is to prov de an improved refractory for contact with molten glass and for other purposes, having a facing composed of zirconium oxid 1ntegrally united to a body or backing of. fire clay, glass-tank block materlal, orother suitable refractory material.

Another object of my invention is to provide an improved refractory body having a facing of zironium oxid un ted by dry-pressing with a backing body of another refractory material.

In making a refractory block according 'to my present invention, ll place a layer of zirconium oxid in the bottom of a suitable mold. Upon this layer I place another layer composed of zirconium oxid mixed with an equal proportion, or other suitable proportion, of the refractory backing material to be employed. Above this 'second layer 1 place su'fiic'ient fire clay or other selected refractory material to complete the block, and I then apply heavy pressure, suitably by hydraulic means, to compact the contents of the mold. The result of this operation is that the facing or zirconium oxid is intimately attached to and formed integral with the refractory backingbody through a blending layer composed of both materialsn The facing cannot be-removed from the backing, because the material of the backing and the material of the facing are partially interpenetrated with each other. All of the materials mentioned should be ground to such fineness-as is suitable for dry-pressing.

For example, an eight-inch fiux'block for glass tanks may be made by this method, having the surface which is to be exposed to the interior of the glass tank consisting of a layer of zirconium oxid one-inch thick, and with the intermediate or blending layer of mixed zirconium oxid and backing another inch in thickness, the remaining six inches being composed of the backing.

The material, when dry-pressed, should Application filed January 20, 1926 Serial No. 82AM.

contain not over 12% of water. 5% or 6% of water in the mixture is suflicient to render the articles rigid and self-sustaining when pressed under hydraulic pressure of the order of two tons per square inch. The

poses may be used as the body of the blocks and other articles made according to my invention. I may also use special refractory mixtures, but the precise nature of the backing material is not an essential feature of the present invention.

A glass tank block faced with zirconium oxid has theadvantage that the facing is not readily attacked by molten glass and the facing thus protects'the body of the block and gives the block long life in service.

A dry-pressed refractory body of the kind described above has low heat conductivity and, therefore, blocks of this kind are, to a considerable degree, self-insulating.

My invention is not limited to the backing materials mentioned herein, nor to the production of any particular shapes.

I claim as my invention:

1. A refractory body having a facing of substantially pure zirconium oxid that is partially interpenetrated with said body and is therefore united integrally therewith. A

2., A refractory body having a facingof zirconium oxid united to a backing material byan intermediate layer composed of zirconium oxid and the backing material. 3. A refractory bodyhaving a facing of zirconium oxid united by dry-pressing to a backing body of refractory material.

4. A refractory body having a facing of an intermediate la er of mixed zirconium zirconium oxid united by dry-pressingto a oxid and the material of said backing body.

fSign'ed at Hartford' Conn, this 31st day of December, 1925. PAULG. WILLETTS. 

